A bis-(1(2)H-tetrazol-5-yl)amine compound is useful as a gas generant, and a known production method uses an azide salt and a dicyanamide salt (for example, see Non-Patent Literature 1 and Patent Literatures 1 to 5).
In the production method described in Non-Patent Literature 1, a reaction is carried out under reflux for 23 hours using trimethylammonium chloride as an acid in an aqueous solvent, and then a treatment with hydrochloric acid is performed, thereby giving bis-(1(2)H-tetrazol-5-yl)amine monohydrate in a yield of 67%.
In the production method described in Patent Literature 1, a reaction is carried out under reflux for 48 hours using boric acid in a large excess in an aqueous solvent, and then a treatment with hydrochloric acid is performed, thereby giving bis-(1(2)H-tetrazol-5-yl)amine anhydrate in a yield of 80.3%.
In the production method described in Patent Literature 2, a reaction is carried out at 100 to 150°C. for 5 to 10 hours using an ammonium halide such as ammonium chloride as an acid in an aprotic solvent such as N,N-dimethylformamide, and then a treatment with hydrochloric acid is performed, thereby giving bis-(1(2)H-tetrazol-5-yl)amine monohydrate in a yield of 80 to 90%.
In the production method described in Patent Literature 3, a reaction is carried out at 95 to 105° C. for 24 hours using a protic acid such as hydrochloric acid and a metal chloride such as manganese chloride in water or a water-miscible solvent, the suspended solids of the metal salt are filtered off, and then a treatment with a protonic acid such as hydrochloric acid is performed, thereby giving bis-(1(2)H-tetrazol-5-yl)amine monohydrate in a yield of 80 to 90%.
In the production method described in Patent Literature 4, an acid having a pKa less than 2 is gradually mixed (usually for 12 to 24 hours) with a reaction solution at 65°C. or greater (desirably under reflux) in an aqueous solvent so as to maintain a high pH to keep the hydrazoic acid within the system. After the reaction, a treatment with a protonic acid such as hydrochloric acid is performed, thereby giving bis-(1(2)H-tetrazol-5-yl)amine monohydrate in a yield of about 86%.
In the production method described in Patent Literature 5, an acid of having a pKa of 3 to 9 is mixed with a reaction solution at 65° C. or greater (desirably under reflux) in an aqueous solvent, and after the reaction, the reaction solution is acidified so as to have a pH less than 3, thereby giving a bis-(1(2)H-tetrazol-5-yl)amine compound.